GM Service Manual Online
For 1990-2009 cars only

Important: Review the system operation in order to familiarize yourself with the system functions. Refer to Brake Warning Lamp Description .

Visual/Physical Inspection

    • Inspect for aftermarket devices which could affect the operation of the Brake Warning System. Refer to Checking Aftermarket Accessories in Wiring Systems.
    • Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
    • Inspect the master cylinder reservoir for the proper brake fluid level.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

    •  Brake Warning Indicator Always On
    •  Brake Warning Indicator Inoperative
    •  Brake Pedal Excessive Travel
    •  Brake Pedal Travel Gradually Increases
    •  Brake Pedal Excessive Effort
    •  Brake Pulsation
    •  Brake Pedal Slow Return
    •  Brake System Slow Response
    •  Brake System Slow Release
    •  Brakes Drag
    •  Braking Action Uneven - Side to Side
    •  Braking Action Uneven - Front to Rear
    •  Brake System Noise with Brakes Applied
    •  Brake System Noise with Brakes Not Applied
    •  Brake System Groan at End of Stop
    •  Vacuum Booster Diagnosis
    •  Vacuum Booster Diagnosis